Channel formation in Pb-Sn, Pb-Sb, and Pb-Sn-Sb alloy ingots and comparison with the system NH < inf> 4 CI-H < inf> 2 O
Document Type
Article
Publication Date
7-1988
Department
Department of Materials Science and Engineering
Abstract
The formation of segregation channels during the unidirectional solidification of base chilled ingots has been studied as a function of composition in binary Pb-Sn and Pb-Sb and ternary Pb-Sn-Sb alloys. The patterns of channel distribution were characterized in the binary and ternary systems and are described as functions of temperature gradients, growth rates, dendrite spacings, and interdendritic permeabilities. Channels appear to nucleate at random across a dendritic front and subsequently to interact as they propagate, decreasing in density across the front. Assuming that the interdendritic spacing is the characteristic distance for a liquid perturbation, yields critical effective Rayleigh numbers which lie within a factor of x40 for both metallic and aqueous systems. This correlation is close, considering the sensitivity to any assumed dimension and the range of material properties involved, and is taken to support a model for channel nucleation occurring close to the dendritic growth front.
Publication Title
Metallurgical Transactions A
Recommended Citation
Sarazin, J.,
&
Hellawell, A.
(1988).
Channel formation in Pb-Sn, Pb-Sb, and Pb-Sn-Sb alloy ingots and comparison with the system NH < inf> 4 CI-H < inf> 2 O.
Metallurgical Transactions A,
19(7), 1861-1871.
http://doi.org/10.1007/BF02645156
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/4399
Publisher's Statement
© 1988 The Metallurgical of Society of AIME. Publisher’s version of record: https://doi.org/10.1007/BF02645156